coronary sinus
collection of veins joined together to form a large vessel that collects blood from the heart muscle
en-GB/kɒɹənɹiː ˈsaɪnəs/
en-US/ˈkɔɹəˌnɛɹi ˈsaɪnəs/
collection of veins joined together to form a large vessel that collects blood from the heart muscle